Regardless, the lowly, ill-regarded diesel engine sits on the verge of making a historic comeback on these shores, and fuel efficiency enthusiasts with a soft spot for performance look to be the greatest benefactors.

Back in the late 70s and early 80s, diesels had a much maligned go 'round the American marketplace. Stinky, noisy, dirty and slow, only the most masochistic commuter partook of the potential MPG lighted by glowplug. We remember with not so fond recollection an olive green VW Rabbit which boasted 52 MPG and an astonishing 18 second 0-60 run. Not the good variety of astonishment, to be sure.

Oh, but how things change. Businessweek paints a possibly rosy picture for the future of diesel-powered sedans and even performance oriented models like BMW's 335. With fuel efficiency at the forefront (diesels burn fuel far more efficiently than gasoline engines) and Prius decimating performance on tap (in some cases gas powered cars are shamed as well), more manufacturers are counting on American consumers to at least consider the oil burner option when buying a new car. Europeans buy diesel powered cars more than half the time, and although congestion fees like those in London are waived for hybrid vehicles, it's predicted most drivers will still prefer the reliability, power and affordability of diesel power.

Diesel sales in the US hover around three percent, represented mostly by trucks and SUVs. But with more diesel sedans planned to hit the market within the next five years, that number should go up significantly. The new low-sulfer blend is also becoming more widely available at filling stations across he country, soon ensuring emissions compliance in all 50 states. Correspondingly, hybrid sales are presently around two percent of all new car sales. More hybrid vehicles entering the supply chain could offset diesels growth here and possibly even slow them abroad, but smart consumers would be wise to consider the virtues and potential pitfalls of all options.

For the time being, hybrids still trump diesels in greenness, boasting exponentially lower emissions, particularly nitrous oxide. Innovations in exhaust design will curb that to some degree, but don't expect any PZEV diesels coming down the pike anytime soon. Do however expect miles per gallon and horsepower numbers to rise, even in comparison to the allegedly fuel sipping hybrids. Allegedly? Just take a look at a recent comparison by The Sunday Times of London  between the hallowed Toyota Prius and a BMW 520d.